The Fanghu Waishi 方壶外史 Outer History of the Square Vase

Fanghu Waishi (Outer History of the Square Vase) is a collection of inner alchemy texts compiled by Lu Xixing, a Taoist priest of the Ming Dynasty. There was an early Ming Dynasty printed edition, which is now rarely traceable; the existing version is a reprinted edition from 1915, based on the Ming edition, published by Zheng Guanying.

Fanghu Waishi is divided into eight volumes, containing fourteen works, which can be roughly categorized into two types:

According to Huang Sui's postscript to Commentary on the Wuzhen Pian, the Ming printed edition of Fanghu Waishi also included Lu Xixing's A Short Preface to the Wuzhen Pian in one volume. If so, the Ming edition would contain fifteen works in total.

Lu Xixing was a highly scholarly inner alchemist of the Ming Dynasty. His commentaries on Taoist classics such as the Cantongqi, Wuzhen Pian, and Yinfujing are straightforward and clearer than those of his predecessors. In inner alchemy, he emphasized the cultivation of both nature and destiny, focusing on the Heavenly Origin (Tianyuan) while also encompassing the Human Origin (Renyuan). He advocated starting practice with foundation building and self-cultivation (zhuji lianji), eliminating desires to perceive one's true nature. As he stated in Explanatory Notes on Qiu Chuji's Song of the Clear Sky: "At the initial stage of learning the Tao, one must first refine the self (lianji). Refining the self means conquering the self—overcoming selfishness, purifying all desires, and when the original nature is clear and bright, one perceives the true nature."

After perceiving the true nature, one collects the medicine and returns it to the furnace, draws from Kan to fill Li, and refines essence into qi. Here, he emphasized the yin-yang of the Human Origin, noting in Treatise on the Mystical Skin: "One must understand that the qi of the other and the self are both divided from the same Taiji. Within them, the essences of yin and yang are hidden in each other's abodes; there are aspects that cannot be cultivated alone."

However, the alchemical formulas he described are not explicitly stated. In On Rectifying the Golden Elixir, he wrote: "The heavenly secrets are extremely profound; without the guidance of a master, who dares to speak recklessly? Let me only open the door, and await your enlightenment."

Lu Xixing strongly denounced the "Three Peaks" sexual cultivation techniques as heretical, clearly distinguishing the Great Origin Tao from such practices. Regarding the life-nurturing practices of the Golden Elixir, he stated: "The true fire has no fixed timing; the great medicine has no fixed measure." He believed there was no need to adhere to cumbersome regulations, emphasizing that inner cultivation should follow nature, "neither forgetting nor forcing." As he put it in Treatise on the Mystical Skin: "In summary, the so-called inner cultivation can be described in one phrase: 'Continuously, as if existing.'"

The late Ming Taoist Puzhen Daoist, in his work Xuanliaozi, highly praised Lu Xixing's alchemical methods, stating: "The East School's techniques for opening the orifices, unfolding the passages, passing through barriers, and ingesting the medicine are more superior and concise than those used in Indian yoga and esoteric Buddhist dual cultivation methods."